In conventional wireless terminals such as mobile phones, carrier aggregation is an aggregation of a plurality of continuous or discontinuous uplink or downlink spectrums and even spectrum fragment carriers together. In this manner, a wider spectrum is achieved, thus increasing the transmission speed. This carrier aggregation can refer to the aggregation of a plurality of downlink spectrums to increase downlink transmission speed or the aggregation of a plurality of uplink spectrums to increase uplink transmission speed.
In a frequency division duplex mode, the uplink band and downlink band of a wireless terminal have the same bandwidth, that is, the wireless terminal has the same uplink transmission bandwidth and downlink receiving bandwidth. However, the uplink data and downlink data requirements of the wireless terminal are usually asymmetric. In other words, the demands of downlink data for transmission speed and data volume are usually larger than that of the uplink data, resulting in a saturated downlink band but an idle uplink band as well as a low utilization rate of the wireless terminal, which results in a serious waste of uplink band resources and inconveniences users.
Therefore, there is a need for an improved data receiving and transmitting method for mobile terminals.